Unlock Bootloaders, Roots, and You
Well, since it’s kinda quite and haven’t really posted much guess I’ll post something. Some people knew I had an Android phone for awhile (since late July 2010) but haven’t really talked much about it. First Android based phone was the Motorola Droid X and about a week and half later learned to root it so I can run AdFree Android. During that time I’ve also learned that the Droid X’s bootloader was locked with eFuse. Further I learned about it the more I started to get interested. I was like, “hmm… the bootloader must be very important if a lot of modders are complaining about the bootloader being locked and how it needs to hijack the boot strap just to load a third party recovery.”
Turns out what I was thinking right because the more I research the more I started to understand what was going on. Since the Motorola XOOM‘s bootloader’s unlockable is where I start learning more (I have a 3G XOOM, still waiting on the 4G upgrade to come out). And I recently upgraded my X to the HTC Thunderbolt and learned that there bootloader is also unlock (by unlocking it through HBOOT flash).
So here I’ll put down what I’ve learned so far.
What Exactly Is A Bootloader?
A bootloader is a piece of code that runs at the low level. You can think of it as the BIOS (Basic Input/Output System) of a computer. It’s purpose is to execute the kernel and OS for actual boot. The bootloader also checks the signature to make sure it’s an official ROM provided by the manufacture assuming that the bootloader is still locked. With an unlocked bootloader you can flash customized ROMs without having to worry about signature checks. This is why having an unlocked bootloader is important.
Because of the fact that Motorola started locking down there bootloader without the option of unlocking it is such a big deal to the modding community. But because of the modding community, they have found a way around it. Just because the bootloader’s locked doesn’t mean you can’t get root access.
What Exactly Is Root?
Root is a user account that has full access and permission to all files and folders of an OS. This means you can do pretty much whatever you want to the OS (in this case the Android OS). I’ve used root access to copy my notification tones and ring tones directly to the phone instead of on the memory card (for a good reason).
Usually to root an Android device you will need to find an exploit and once you exploit it you can then gain perm. root access. This is how it was done with the Droid X in Android 2.1 there was an exploit where if you toggle on/off either the WiFi or Bluetooth after running one command you’d be able to gain temp root access so you can copy all the files you need for perm root. Because of the fact that the Droid X’s bootloader isn’t unlockable we had to make due with that.
With the XOOM, since the bootloader’s unlockable, once you unlock the bootloader all you had to do was flash a new system image which already included root access.
For the HTC Thunderbolt, you had to gain temp root to downgrade, once downgraded you can then flash a new image that will turn S-ON to S-OFF (S meaning Secure, meaning the bootloader is either checking signatures or not) before upgrading back up with perm root.
So, has you can see, the ways of rooting an Android device varies. But as long as the bootloader’s unlocked, you can get root pretty easy and flash custom kernels and ROMs. Because the Droid X and all newer Motorola phone’s bootloader will never be unlockable, you won’t be able to load true custom ROMs but can make due because of the modding community.
What Exactly Is A ROM?
A ROM, in Android’s case, is the actual system. It’s pretty much the changes to the /system directory customized to either be less bloated or to be speed up the performance. This will sometimes includes changes to kernel itself but you won’t be able to change the kernel if the bootloader is locked and cannot be unlocked. Changes to the kernel sometimes makes improvements of the overall stability and/or performance as well.
Think of the ROM as a different flavor of an Linux OS (assuming you know something of the Linux OS, even if you’ve just heard of Red Hat and Mandrake) is the easiest way to explain I can think of.
And The Recovery?
The recovery (located on the recovery partition) is used for trying to recovery your phone. Basic recovery is usually a way for formatting the phone and allows for software updates. On a rooted/unlocked bootloader device, you can flash a custom recovery (or in terms of the Motorola Droid X, Droid X2, Droid 2, etc, using a bootstrap to hijack the recovery call) for more options such as backing up the whole phone (current ROM), flashing customized flashable zip files (such as adding themes or different ROM), etc.
Questions To You
Weren’t you using a Blackberry before?
Yes, I was, and loved it, but then after I gotten used to my Droid X and saw what I can do, I just tossed my Blackberry to my mom. My mom loves my old Blackberry so it worked out for her.
But You only had your X for less then a year? What gives?
Multiple co-workers and friends gotten it, the more I played with it, the more I wanted it, called Verizon, and they gave me a really good deal for it with the extended battery. Can turn down an awesome offer.
You said you have a XOOM? Why you didn’t say anything?
I was typing up a post about it on the XOOM itself but became too lazy. I will say this, though. Android 3.1 (Honeycomb) is fucken awesome!
How you liking the Thunderbolt?
The Thunderbolt is awesome, even more so now that I don’t have to experiences the random reboots (that started happening yesterday, June 12th) because of the new radio I’ve flashed and am using Flyweight ROM.
Anyways, can’t really think of much more to say but if you have any questions let me know in a comment or email.